Out-Of-Plane Magnetic Domain Structure In A Thin Film Of La(0.67)Sr(0.33)Mno(3) On Srtio(3) (001) Observed By Magnetic Force Microscopy

The room temperature out-of-plane magnetization of epitaxial thin films of La(0.67)Sr(0.33)MnO(3) on SrTiO(3) (001) has been investigated with magnetic force microscopy, using magnetic tips with very small coercivity, relative to the film. A clear magnetic pattern in the form of a checkerboard, with domain dimensions of a few hundred nanometers, was found for the thin, coherently strained films, which is approximately aligned along the maximum strain [110] and [110] directions in the film. With increasing in-plane applied magnetic field, the magnetic contrast reduces, reflecting the rotation of the magnetization vector into the plane of the film. This process is reversible with the field. The out-of-plane magnetic pattern is not sensitive to rotation of the in-plane field. We attribute the observed out-of-plane magnetization component to an out-of-plane magnetic anisotropy, which is a remainder of the [111] magnetic easy axis in bulk La(0.67)Sr(0.33)MnO(3) single crystal.